ALBERT

Description: We examined the relationships between large wood (LW) export and precipitation patterns and intensity by analyzing the data on the annual volume of LW removed from 42 reservoirs and the daily precipitation at or near the reservoir sites. We also calculated the effective precipitation by considering the antecedent precipitation. Both daily and effective precipitation data were used as explanatory variables to explain LW export. The model selection revealed that the precipitation pattern and intensity controlling LW export varied with latitude in the Japanese archipelago. In small watersheds with narrow channel widths and low discharges, mass movements, such as landslides and debris flows, are major factors in the production and transport of LW. In this case, the effective precipitation required to initiate mass movements regulated the LW export and did not vary with the latitude. In intermediate and large watersheds with wide channel widths and high stream discharges, heavy rainfall and subsequent floods regulated buoyant depth, influencing the initiation of LW movement. In southern and central Japan, intense rainfall accompanied by typhoons or localized torrential downpours causes geomorphic disturbances, which introduce abundant pieces of LW into the channels. However, these pieces continue to be removed by repeated rainfall events. Therefore, LW export is supply-limited and potentially produces less LW accumulation. Conversely, in northern Japan, where typhoons and torrential downpours are rare, LW export is transport-limited because LW pieces recruited by bank erosion, tree mortality, and windthrow accumulate and persist on valley floors. These pieces may be easily exported by infrequent flooding.

Description: We developed a method to measure in situ the isotopic composition of liquid water with minimal supervision and, most important, with a temporal resolution of less than a minute. For this purpose a microporous hydrophobic membrane contactor (Membrana) was combined with an isotope laser spectrometer (Picarro). The contactor, originally designed for degassing liquids, was used with N2 as a carrier gas in order to transform a small fraction of liquid water to water vapor. The generated water vapor was then analyzed continuously by the Picarro analyzer. To prove the membrane's applicability, we determined the specific isotope fractionation factor for the phase change through the contactor's membrane across an extended temperature range (8°C–21°C) and with different waters of known isotopic compositions. This fractionation factor is needed to subsequently derive the liquid water isotope ratio from the measured water vapor isotope ratios. The system was tested with a soil column experiment, where the isotope values derived with the new method corresponded well (R2 = 0.998 for δ18O and R2 = 0.997 for δ2H) with those of liquid water samples taken simultaneously and analyzed with a conventional method (cavity ring-down spectroscopy). The new method supersedes taking liquid samples and employs only relatively cheap and readily available components. This makes it a relatively inexpensive, fast, user-friendly, and easily reproducible method. It can be applied in both the field and laboratory wherever a water vapor isotope analyzer can be run and whenever real-time isotope data of liquid water are required at high temporal resolution.

Description:    This study examines biophysical and socio-demographic factors potentially affecting water use patterns of households with mandatory rainwater tanks in South East Queensland (SEQ). The Queensland Development Code (QDC) MP 4.2 promotes the use of rainwater tanks at the domestic level to reduce direct reliance on mains water supply. A sample of 1,134 mandated rainwater tank households were surveyed across SEQ. Results indicated that the majority of participants (78%) had tanks of 5 kL in capacity or larger, with 35% of householders having at least half of roof catchment area connected to their tanks. Also, the majority of participants utilised their rainwater for toilet flushing (97%), clothes washing (94%) and garden irrigation (77%). These biophysical findings indicate a high level of compliance with the QDC MP 4.2 code. Social factors affecting potential yields from mandated rainwater tanks were also examined, to complement the biophysical data obtained. It was found that the majority of tank users were happy to use rainwater as an alternative water supply option for non-potable uses. However, most participants reported being unaware of past or present water restrictions to their water supply, highlighting important social implications for total mains water savings. In conclusion, this study presents important biophysical and social descriptions about mandated water users in urban SEQ, as well as providing a foundation for future modelling of actual yields from mandated rainwater tanks to facilitate improved assessment of mains water savings due to the implementation of mandated rainwater tanks. Content Type Journal Article Pages 1-16 DOI 10.1007/s11269-012-0003-7 Authors Aditi Mankad, CSIRO Ecosystem Sciences, GPO Box 2583, Brisbane, QLD 4001, Australia Meng Nan Chong, CSIRO Land and Water, 41 Boggo Road, Dutton Park, Brisbane, QLD 4102, Australia Ted Gardner, CSIRO Land and Water, 41 Boggo Road, Dutton Park, Brisbane, QLD 4102, Australia Ashok Sharma, CSIRO Land and Water, Highett, VIC 3109, Australia Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description: Transit time of discharge is a hydrological characteristic used in water resource management. Previous studies have demonstrated large spatial variation in the mean transit time (MTT) of stream base flow in meso-scale catchments. Various relationships between topography and MTT have been reported. Although it is generally assumed that base flow MTT is controlled by the depth of the hydrologically active layer that recharges a stream, this hypothesis has not been tested in field studies. This study confirmed that the depth of hydrologically active soil and bedrock controls spatial variation in MTT. The study used isotopic and geochemical tracer data gathered in the 4.27 km2 Fudoji catchment, central Japan. The results, together with previously documented relationships between topography and MTT, indicate that the depth of the hydrologically active layer is sometimes, but not always, related to topography. A comprehensive understanding of the factors that control base flow production in mountainous catchments will require further study of the water flow path depths that recharge streams.

Description:    Monitoring the temporal variations of reference evapotranspiration (ET o ) and quantifying any trends offer valuable information for regional hydrology, agricultural water requirements and water resources management. This study aimed to examine the temporal trends in the Penman–Monteith ET o in the west and southwest of Iran by using the Kendall and Spearman tests after eliminating the influence of significant lag-1 serial correlation from the ET o time series. The magnitudes and starting years of significant ET o trends were determined by the Mann-Kendall rank statistic and the Theil–Sen’s estimator, respectively. For the study period of 1966–2005, a significant positive lag-1 serial correlation coefficient was observed at almost all the stations. The existence of the positive serial correlation in the ET o series increased the possibility of the Kendall and Spearman tests to reject the null hypothesis of no trend while it is true. It was found that the Kendall test was more sensitive than the Spearman test to the existence of the positive serial correlation in the ET o series. After removing the serial correlation effect with pre-whitening method, only three significant increasing ET o trends were obtained at Khorram-Abad, Shahrekord and Zanjan stations at the rates of 0.16, 0.06 and 0.06 mm/day per decade, respectively. The significant increasing ET o trends of Khorram-Abad, Zanjan and Shahrekord stations started in 1997, 1994 and 1998, respectively. The stepwise regression method showed that wind speed was the most dominating variable affecting on the significant changes of ET o . Content Type Journal Article Pages 1-14 DOI 10.1007/s11269-012-0011-7 Authors Hossein Tabari, Department of Water Engineering, Ayatollah Amoli Branch, Islamic Azad University, Amol, Iran Jaefar Nikbakht, Department of Water Engineering, Zanjan University, Zanjan, Iran P. Hosseinzadeh Talaee, Young Researchers Club, Hamedan Branch, Islamic Azad University, Hamedan, Iran Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    This paper employs the newly-developed convergence tests introduced by Phillips and Sul (Econometrica 75:1771–1855, 2007 ) to investigate convergence of real GDP per capita across Canadian provinces, as well as the transitional path of factors behind the convergence or divergence pattern. In contrast with previously published studies on Canadian provincial convergence, the analysis carried out in this paper allows for heterogeneous technology and reveals that Canadian provinces are characterized by distinct convergent clubs, that is, separate convergence clubs that converge to different steady states. We make the case that the findings presented in this paper are of utmost importance for Canadian policy-makers as they seek to develop effective policy measures to address regional economic disparities. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s00168-012-0500-x Authors Mahamat Hamit-Haggar, Investment and Capital Stock Division, Statistics Canada, Ottawa, ON K1A 0T6, Canada Journal The Annals of Regional Science Online ISSN 1432-0592 Print ISSN 0570-1864

Description:    Providing enhanced satellite positioning as a web service can be an effective way to enable low-level GPS receivers to perform surveys with a good accuracy and to reduce hardware cost, by removing computation capability and embedded proprietary software. goGPS is an open source application for achieving sub-meter accuracy with low-cost GPS receivers by exploiting real-time kinematic positioning, Kalman filtering, aid from a digital terrain model, and in general by integrating GPS data with other sources of information. Since goGPS directly processes raw GPS observations, it provides a means to substitute black-box processing components (e.g., GPS chipsets) with open source positioning software. goGPS can work either in real-time or post-processing, by acquiring raw GPS data in input and providing positioning (i.e., coordinates) in output. Though originally developed in MATLAB, goGPS was recently ported to Java in order to have the possibility to provide it as a web service, thus allowing a wider user base to develop and use it. Since real-time GPS positioning heavily relies on fast matrix computation, a careful selection of Java matrix libraries was carried out in order to obtain optimal performances. An Open Geospatial Consortium standard Web Processing Service (WPS) implementation of goGPS by means of ZOO WPS framework was developed and tested in order to let lightweight clients just acquire raw GPS data, send them to a server for processing, and receive back the accurate positioning. Content Type Journal Article Category Original Paper Pages 1-8 DOI 10.1007/s12518-012-0081-5 Authors Eugenio Realini, Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji City, 611-0011 Kyoto, Japan Daisuke Yoshida, Faculty of Liberal Arts, Tezukayama Gakuin University, 2-1823 Imakuma, Osakasayama City, 589-8585 Osaka, Japan Mirko Reguzzoni, DIIAR, Politecnico di Milano, P.zza Leonardo da Vinci 32, 20133 Milano, Italy Venkatesh Raghavan, Graduate School for Creative Cities, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, 558-8585 Osaka, Japan Journal Applied Geomatics Online ISSN 1866-928X Print ISSN 1866-9298

Description:    Mit der Erarbeitung einer makroregionalen Anpassungsstrategie für den Ostseeraum hat die Europäische Union eine neue strategische Ebene in die Diskussion zur Anpassung an die Folgen des Klimawandels eingebracht. Basierend auf empirischen Sondierungen in drei Stadtregionen im Ostseeraum – Stockholm (Schweden), Rostock (Deutschland) und Riga (Lettland) – wird diskutiert, welchen Beitrag und Mehrwert transnationale Kooperationen bei der Anpassung an den Klimawandel leisten können und welche Aufgaben auf der lokalen und regionalen bzw. auf der transnationalen Ebene erfüllt werden können. Im Rahmen der empirischen Betrachtungen wurden Dokumente ausgewertet, semistrukturierte Interviews mit Experten und eine teilnehmende Beobachtung innerhalb eines Szenarioprozesses durchgeführt. Die exemplarisch dargestellten Anpassungsprozesse deuten darauf hin, dass eine transnationale Kooperation die lokalen und regionalen Aktivitäten zur Anpassung an die Folgen des Klimawandels sinnvoll ergänzen kann. Ein gezielter Erfahrungsaustausch zwischen Stadtregionen mit ähnlichen Problemlagen, aber auch Sensibilisierungsprozesse im Hinblick auf das Thema Anpassung können einen Mehrwert für die Beteiligten darstellen, insbesondere dann, wenn diese Kooperation Ebenen überspannend konstruiert und der Austauschprozess strukturiert auf das Ziel eines gemeinsamen Lern- und Innovationsprozesses ausgerichtet wird. Allerdings scheint der Mehrwert transnationaler Kooperation insbesondere hinsichtlich einer Einflussnahme auf lokale Aktivitäten und vor dem Hintergrund institutioneller Rahmenbedingungen begrenzt. Content Type Journal Article Category Wissenschaftlicher Beitrag Pages 1-14 DOI 10.1007/s13147-012-0152-4 Authors Sonja Deppisch, HafenCity Universität Hamburg, Winterhuder Weg 31, 22085 Hamburg, Deutschland Meike Albers, HafenCity Universität Hamburg, Winterhuder Weg 31, 22085 Hamburg, Deutschland Journal Raumforschung und Raumordnung Online ISSN 1869-4179 Print ISSN 0034-0111

Description:    We present a novel approach for calibration of stochastic discontinuity network parameters based on genetic algorithms (GAs). To validate the approach, examples of application of the method to cases with known parameters of the original Poisson discontinuity network are presented. Parameters of the model are encoded as chromosomes using a binary representation, and such chromosomes evolve as successive generations of a randomly generated initial population, subjected to GA operations of selection, crossover and mutation. Such back-calculated parameters are employed to make assessments about the inference capabilities of the model using different objective functions with different probabilities of crossover and mutation. Results show that the predictive capabilities of GAs significantly depend on the type of objective function considered; and they also show that the calibration capabilities of the genetic algorithm can be acceptable for practical engineering applications, since in most cases they can be expected to provide parameter estimates with relatively small errors for those parameters of the network (such as intensity and mean size of discontinuities) that have the strongest influence on many engineering applications. Content Type Journal Article Category Original Paper Pages 1-13 DOI 10.1007/s00603-012-0226-1 Authors R. Jimenez, Technical University of Madrid, ETSI Caminos, Canales y Puertos, C/ Profesor Aranguren s/n, 28040 Madrid, Spain R. Jurado-Piña, Technical University of Madrid, ETSI Caminos, Canales y Puertos, C/ Profesor Aranguren s/n, 28040 Madrid, Spain Journal Rock Mechanics and Rock Engineering Online ISSN 1434-453X Print ISSN 0723-2632

Description: Monitoring and Analysis of the Mining-Induced Ground Movement in the Longshou Mine, China Content Type Journal Article Category Technical Note Pages 1-5 DOI 10.1007/s00603-012-0232-3 Authors Haijun Zhao, Key Laboratory of Engineering Geomechanics, Institute of Geology and Geophysics, Chinese Academy of Sciences, 100029 Beijing, China Fengshan Ma, Key Laboratory of Engineering Geomechanics, Institute of Geology and Geophysics, Chinese Academy of Sciences, 100029 Beijing, China Yamin Zhang, Key Laboratory of Engineering Geomechanics, Institute of Geology and Geophysics, Chinese Academy of Sciences, 100029 Beijing, China Jie Guo, Key Laboratory of Engineering Geomechanics, Institute of Geology and Geophysics, Chinese Academy of Sciences, 100029 Beijing, China Journal Rock Mechanics and Rock Engineering Online ISSN 1434-453X Print ISSN 0723-2632

Description:    Different failure modes during fracture shearing have been introduced including normal dilation or sliding, asperity cut-off and degradation. Attempts have been made to study these mechanisms using analytical, experimental and numerical methods. However, the majority of the existing models simplify the problem, which leads to unrealistic results. With this in mind, the aim of this paper is to simulate the mechanical behaviour of synthetic and rock fracture profiles during direct shear tests by using the two-dimensional particle flow computer code PFC2D. Correlations between the simulated peak shear strength and the fracture roughness parameter D R1 recently proposed by Rasouli and Harrison ( 2010 ) are developed. Shear test simulations are carried out with PFC2D and the effects of the geometrical features as well as the model micro-properties on the fracture shear behaviour are studied. The shear strength and asperity degradation processes of synthetic profiles including triangular, sinusoidal and randomly generated profiles are analysed. Different failure modes including asperity sliding, cut-off, and asperity degradation are explicitly observed and compared with the available models. The D R1 parameter is applied to the analysis of synthetic and rock fracture profiles. Accordingly, correlations are developed between D R1 and the peak shear strength obtained from simulations and by using analytical solutions. The results are shown to be in good agreement with the basic understanding of rock fracture shear behaviour and asperity contact degradation. Content Type Journal Article Category Original Paper Pages 1-27 DOI 10.1007/s00603-012-0231-4 Authors Mohammad Sadegh Asadi, Baker Hughes, Perth, WA, Australia Vamegh Rasouli, Curtin University, Perth, WA, Australia Giovanni Barla, Politecnico di Torino, Torino, Italy Journal Rock Mechanics and Rock Engineering Online ISSN 1434-453X Print ISSN 0723-2632

Description: Statistical Method for Assessing the Uniaxial Compressive Strength of Carbonate Rock by Schmidt Hammer Tests Performed on Core Samples Content Type Journal Article Category Technical Note Pages 1-8 DOI 10.1007/s00603-012-0230-5 Authors G. Bruno, Department of Water Engineering and Chemistry, Technical University of Bari, Bari, Italy G. Vessia, Consiglio Nazionale delle Ricerche, Istituto di Ricerca per la Protezione Idrogeologica, Via Amendola 122, 70126 Bari, Italy L. Bobbo, Freelance Civil Engineer, Bari, Italy Journal Rock Mechanics and Rock Engineering Online ISSN 1434-453X Print ISSN 0723-2632

Description:    The objective of this article is to study as extensively as possible the uncertainties affecting the annual energy produced by a windmill. In the literature, the general approach is to estimate the mean annual energy from a transformation of a Weibull distribution law. Then the issue is reduced to estimating the coefficients of this distribution. This is obtained by classical statistical methods. Therefore, the uncertainties are mostly limited to those resulting from the statistical procedures. But in fact, the real uncertainty of the random variable which represents the annual energy cannot been reduced to the uncertainty on its mean and to the uncertainties induced from the estimation procedure. We propose here a model, which takes advantage of the fact that the annual energy production is the sum of many random variables representing the 10 min energy production during the year. Under some assumptions, we make use of the central limit theorem and show that an intrinsic uncertainties of wind power, usually not considered, carries an important risk. We also explain an observation coming from practice that the forecasted annual production is always overestimated, which creates a risk of reducing the profitability of the operation. Content Type Journal Article Category Original Paper Pages 1-14 DOI 10.1007/s00477-012-0565-1 Authors Alain Bensoussan, School of Management, University of Texas, Dallas, TX, USA Pierre Raphaël Bertrand, INRIA Saclay, 91893 Orsay Cedex, France Alexandre Brouste, Laboratoire Manceau de Mathématiques, Université du Maine, Le Mans Cedex, France Journal Stochastic Environmental Research and Risk Assessment Online ISSN 1436-3259 Print ISSN 1436-3240

Description: This paper examines the long-term historical changes in frequency and amplitude of hydroclimatic extremes in the Blue Nile basin using data from the second half of 20th century. The temporal variability of basin-wide rainfall extremes and river flow extremes from four gauging stations was investigated under the hypothesis of no trend and no persistence in time. On the basis of a quantile anomaly analysis method, decadal variations in extreme daily, monthly, and annual quantiles were studied, and the periods of statistical significance were identified. The analysis showed that high and low river flows and rainfall depths do not vary in time in a fully random way but show a particular variation pattern. Their extremes show significant decadal variations. The 1980s had statistically significant negative anomalies in extremes in comparison with the long-term reference period of 1964–2009, while the 1960s–1970s and the 1990s–2000s had positive anomalies, although less significant. There is neither consistent increasing nor decreasing trend in rainfall and flow extremes of recent years. Therefore, anticipated trends due to global warming could not be identified. Conversely, low-flow extremes show an increasing trend during the last decade, which could be related to the effect of water regulation works at the outlet of Lake Tana. Moreover, similar patterns and statistically significant correlations were found between climatic indices representing the Pacific and Atlantic Oceans and the Blue Nile rainfall and flow extremes. Changes that occur on the Pacific Ocean appear to be a main driver for the decadal oscillations in climate and related high and low Blue Nile water availability for Ethiopia, Sudan, and Egypt.

Description: Few studies exist on infiltration processes in badlands, although infiltration and subsurface lateral flows are known to contribute to soil erosion and to control slope instability. Our investigation was carried out in a 100 m² plot located in a 0.5 ha landslide in black marls (South-East France). An artificial sprinkling was performed with an intensity of 10 mm.h -1 during 66.4 h interrupted with 8.4 h. breaks. KBr and KCl were used as tracers. A pseudo-steady state was reached after 25-35 hours and 250-350 mm of rainfall. The runoff coefficient was 40% (ratio total runoff volume/total sprinkling water amount). Pre-event water (PE) contributed to the groundwater recharge at the very beginning of the experiment but PE contribution dropped steadily while the soil was saturating. After around 200 mm cumulative rainfall, PE contribution started to rise steeply before reaching a nearly constant value. This original mechanism implies an efficient transfer process of PE. It was assumed from the description of the material structure and from hydrological evidences that PE was mainly drained from a structure porosity made of the marl's flaked nature. Total pre-event water contributions ranged from 25 to 79 % (PE contribution was over 50 % in 2/3 of the observations wells). Over the recession phase, release of pre-event water occurred from the drainage of a texture porosity. The study showed that at the plot scale, infiltration processes proved well organised despite the high heterogeneity and anisotropy of the material. It was possible to propose a general conceptual model explaining the hydrological processes over time and area. The peculiar structure of regolith originating from black marl is preserved over a large part of the weathering time, so that the material structure (type, orientation of grains, small/large pores) remains a first order control of water flow generation in Black marl soils. Copyright © 2012 John Wiley & Sons, Ltd.

Description: In this work, the multifractal properties of hourly rainfall data recorded at a location in Southern Spain have been related to the scale properties of the corresponding Intensity-Duration-Frequency (IDF) curves. Four parametric models for the IDF curves have been fitted to the quantiles of rainfall obtained by using the Generalized Pareto frequency distribution function with the extreme data series obtained for the same place. The scaling of the rainfall intensity moments has been analysed and the empirical moments scaling exponent function has been obtained. The corresponding values of q 1 and γ 1 have been empirical and theoretically calculated and compared to some characteristics of the different IDF models. Thus, the scaling behaviour of IDF curves has been analysed and the best model has been selected. Copyright © 2012 John Wiley & Sons, Ltd.

Description:    In order to protect infrastructures against rockfalls, civil-engineered mitigation measures are widely used. Flexible metallic fences are particularly well suited to stop the propagation of blocks of rock whose kinetic energy can reach 5000 kJ before impact. This paper focuses on the design of highly flexible rockfall fences under the new European guideline ETAG027. The experimental testing and the numerical modeling using the discrete element method (DEM) of a new metallic rockfall fence are presented. Several scales of study were considered; the mesh, the net and the entire structure. The calibration of the DEM models is described and a parametrical study is proposed. The latter aims to underline the type of information that can be obtained from numerical simulations of such a system to enhance its design. Content Type Journal Article Category Original Paper Pages 1-16 DOI 10.1007/s00603-012-0222-5 Authors D. Bertrand, INSA Lyon, L.G.C.I.E. (Laboratoire de Génie Civil et d’Ingéniérie Environnementale), Site Coulomb 2, 69621 Villeurbanne cedex, France A. Trad, INSA Lyon, L.G.C.I.E. (Laboratoire de Génie Civil et d’Ingéniérie Environnementale), Site Coulomb 2, 69621 Villeurbanne cedex, France A. Limam, INSA Lyon, L.G.C.I.E. (Laboratoire de Génie Civil et d’Ingéniérie Environnementale), Site Coulomb 2, 69621 Villeurbanne cedex, France C. Silvani, INSA Lyon, L.G.C.I.E. (Laboratoire de Génie Civil et d’Ingéniérie Environnementale), Site Coulomb 2, 69621 Villeurbanne cedex, France Journal Rock Mechanics and Rock Engineering Online ISSN 1434-453X Print ISSN 0723-2632

Description:    Scarcity of water is now the biggest threat in many parts of the world, specially in arid and semi arid regions. Establishing balance between water resources and the demands in a catchment scale basis could be one of the most important strategies to overcome this problem. In this regard, determination and analysis of water balance components (inputs and outputs) would be necessary. This study has focused on estimation of water balance components in arid-mountainous catchment of Manshad in Yazd province of Iran, during the year 2006–2007 using remote sensing and GIS techniques. To estimate actual evapotranspiration (ET a ) of the catchment, time series of MODIS images were obtained and used via Surface Energy Balance Algorithm for Land (SEBAL) approach. Measured precipitation (P) and runoff (R) data of the catchment were also used to calculate water balance equation components. Results indicated that a large volume of catchment water (about 70%) is wasted through evapotranspiration, while the rainfall is not enough to compensate this volume of water during the year. It seems that the negative (descending) trend has become dominant to the water budget of the area and gradually moves to harsh conditions of water shortage in future decades. Therefore, some actions would be necessary to overcome the problem. Water conservation strategies‚ improvement of water use efficiency, and control on agricultural field expansions are some solutions that could be advised for the studied catchment. Content Type Journal Article Pages 1-12 DOI 10.1007/s11269-012-9999-y Authors Mohammad Taghi Dastorani, Faculty of Natural Resources, Yazd University, Yazd, Iran Samaneh Poormohammadi, Faculty of Natural Resources, Yazd University, Yazd, Iran Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    As there is a limited availability of information on the domestic water consumption through kitchen taps, data collected in a study on dishwashing habits in four European countries has been analysed to gather common habits in the water end-use of households. This paper provides empirical data based on water consumption measurements in 81 households. With the help of a simultaneous webcam observation of the kitchen sink, it was possible to assign the metered consumption data to a specific water use, such as cleaning, drinking or cooking. Water end-use has been analysed with this approach at a very deep level. The study shows that there are, in some measure, large country-specific differences in diurnal water use, as well as in the composition of kitchen activities. Furthermore, the research findings indicate that small households use much more water per person and day than bigger households. This is rather important as demographic shifts are causing a decreased average household size - particularly in urban areas - and, therewith, a growing demand. Water-saving measures at the household and individual level should meet this trend. This paper, therefore, also provides information on to what extent particular kitchen tasks are influential for water consumption in the kitchen, respectively, which activities are important to concentrate on for consumer advice regarding water conservation. Content Type Journal Article Pages 1-11 DOI 10.1007/s11269-012-9976-5 Authors Christian Paul Richter, University of Bonn/Germany, Institute of Agricultural Engineering, Section Household and Appliance Technology, Nussallee 5, 53115 Bonn, Germany Rainer Stamminger, University of Bonn/Germany, Institute of Agricultural Engineering, Section Household and Appliance Technology, Nussallee 5, 53115 Bonn, Germany Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    In this work, we address the mismatch in spatio-temporal resolution between individual, point-location based exposure and grid cell based air quality model predictions by disaggregating the grid model results. Variability of PM 10 point measurements was modelled within each grid cell by the exponential variogram, using point support concentration measurements. Variogram parameters were estimated over the study area globally using constant estimates, and locally by multiple regression models using traffic, weather and land use data. Model predictions of spatio-temporal variability were used for geostatistical unconditional simulation, estimating the deviation of point values from grid cell averages on GPS tracks. The distribution of deviations can be used as an estimate of uncertainty for individual exposure. Results showed a relevant impact of the disaggregation uncertainties compared to other uncertainty sources, dependent of the model used for spatio-temporal variability. Depending on individual behaviour and variability of the pollutant, these uncertainties average out again over time. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s00477-012-0578-9 Authors Lydia E. Gerharz, Institute for Geoinformatics, University of Muenster, Weseler Str. 253, 48151 Münster, Germany Edzer Pebesma, Institute for Geoinformatics, University of Muenster, Weseler Str. 253, 48151 Münster, Germany Journal Stochastic Environmental Research and Risk Assessment Online ISSN 1436-3259 Print ISSN 1436-3240

Description: Major-ion compositions of groundwater are employed in this study of the water-rock interactions and hydrogeochemical evolution within a carbonate aquifer system. The groundwater samples were collected from boreholes or underground tunnels in the Ordovician limestone of Yanzhou Coalfield where catastrophic groundwater inflows can be hazardous to mining and impact use of the groundwater as a water supply. The concentration of TDS ranged from 961 to 3,555 mg/l and indicates moderately to highly mineralized water. The main water-type of the middle Ordovician limestone groundwater is Ca-Mg-SO 4 , with SO 4 2- ranging from 537 mg/l to 2,297 mg/l, and average values of Ca 2+ and Mg 2+ of 455.7 mg/l and 116.6 mg/l, respectively. The water samples were supersaturated with respect to calcite and dolomite and undersaturated or saturated with respect to gypsum. Along the general flow direction, deduced from increases of TDS and Cl - , the main water-rock interactions that caused hydrogeochemical evolution of the groundwater within the aquifer were the dissolution of gypsum, the precipitation of calcite, the dissolution or precipitation of dolomite, and ion exchange. Ion exchange is the major cause for the lower mole concentration of Ca 2+ than that of SO 4 2- . The groundwater level of Ordovician aquifer is much higher than that of C-P coal-bearing aquifers, so the potential flow direction is upward and the pyrite in coal is not a possible source of sulfate, additional data on the stable sulfur and oxygen isotopic composition of the sulfate may be helpful to identify its origin. Although ion exchange probably accounts for the higher mole concentration of Na + than that of Cl - , the dissolution of aluminosilicate can not be ruled out. The data evaluation methods and results of this study could be useful in other areas to understand flow paths in aquifers and to provide information needed to identify the origin of groundwater. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Quantitative evaluation of the effect of climate variability and human activities on runoff is of great importance for water resources planning and management in term of maintaining the ecosystem integrity and sustaining the society development. In this paper, hydro-climatic data from 4 catchments (i.e., Luanhe River Catchment, Chaohe River Catchment, Hutuo River Catchment and Zhanghe River Catchment) in the Haihe River Basin from 1957–2000 were used to quantitatively attribute the hydrological response (i.e., runoff) to climate change and human activities separately. To separate the attributes, the temporal trends of annual precipitation, potential evapotranspiration (PET) and runoff during 1957–2000 were first explored by the Man-Kendall test. Despite that only Hutuo River Catchment was dominated by significant negative trend in annual precipitation, all four catchments presented significant negative trend in annual runoff varying from −0.859 mm a -1 (Chaohe River) to −1.996 mm a -1 (Zhanghe River). Change points in 1977 and 1979 are detected by precipitation-runoff double cumulative curves method and Pettitt's test for Zhanghe River and other three rivers, respectively, and are adopted to divide data set into two study periods as the pre-change period and post-change period. Three methods including hydrological model method, hydrological sensitivity analysis method and climate elasticity method were calibrated with the hydro-climatic data during the pre-change period. And then, hydrological runoff response to climate variability and human activities were quantitatively evaluated with the help of the three methods and based on the assumption that climate and human activities are the only drivers for streamflow and are independent to each other. Similar estimates of anthropogenic and climatic effects on runoff for catchments considered can be obtained from the three methods. We found that human activities were the main driving factors for the decline in annual runoff in Luanhe River Catchment, Chaohe River Catchment and Zhanghe River Catchment, accounting for over 50% of runoff reduction. However, Climate variability should be responsible for the decrease in annual runoff in the Hutuo River Catchment. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Measurements of river water quality at Haridwar, India, taken during 2005 – 2006 show that the river water does not meet the WHO and Bureau of Indian Standards criteria of drinking water quality, especially with respect to total coliform and fecal-coliform. This study investigates the removal of pathogens at a river bank filtration (RBF) site in Haridwar. Using the quality of river water and the quality of abstracted water from a nearby production well, semi-empirical models based on the concept of filtration coefficient are developed and tested for their effectiveness in removing pathogens under varying bacteriological quality of source water. A two-tier model which includes the effect of clogged layer is developed to obtain an equivalent filtration coefficient. This coefficient is found to be linearly related with natural logarithm of the concentration of pathogens in the source water. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Nonpoint source pollution and hydromodification are the leading causes of impairment to our nation's rivers and streams. Roadside ditch networks, ubiquitous in both rural and urban landscapes, intercept and shunt substantial quantities of overland runoff and shallow groundwater to stream systems. By altering natural flowpaths, road ditches contribute not only to hydromodification but also potentially to nonpoint-source (NPS) pollution by acting as hydrologic links between agricultural fields and natural streams. Unfortunately, the impacts of these alterations on watershed hydrology and water quality are not well understood. Through a series of field measurements, including field surveys and discharge monitoring, this study examined the effect of road ditch networks on basin morphometry, field- and watershed-scale hydrology, and pollutant transport in a 38 km 2 agricultural watershed in south-central NY. Salient findings include: (i) 94% of road ditches discharged directly to natural streams, effectively doubling the drainage density, (ii) on average, road ditches increased peak and total event flows in their receiving streams by 78% and 57%, respectively, but displayed significant variation across ditches, (iii) ditches intercepted large quantities of surface and subsurface runoff from agricultural fields and therefore represent efficient conduits for the transport of agricultural NPS pollutants to sensitive receiving waterbodies. Our results provide useful information for hydrologists who wish to further understand how artificial drainage may be affecting watershed hydrology and for managers and engineers tasked with designing appropriate flood and NPS pollution control measures. Copyright © 2012 John Wiley & Sons, Ltd.

Description: We coupled the process-based NIES Integrated Catchment-based Eco-hydrology (NICE) model to an urban canopy model (UCM) and the Regional Atmospheric Modeling System (RAMS) in order to simulate the effect of urban geometry and anthropogenic exhaustion on the hydrothermal changes in the atmospheric/land and the interfacial areas of the Japanese megalopolis. The simulation was conducted with multi-scale in horizontally regional–urban–point levels, and in vertically atmosphere–surface–unsaturated–saturated layers. The model reproduced reasonably the observed hydrothermal values by using ground-truth data in various types of natural/artificial land covers. The simulated results also suggested that the latent heat flux in new water-holding pavement (consisting of porous asphalt and water-holding filler made of steel by-products based on silica compound) has a strong impact on hydrologic cycle and cooling temperature in comparison with the observed heat budget by newly incorporating the effect of water amount on the heat conductivity in the pavement. Furthermore, the model predicted the hydrothermal changes under two types of land cover scenarios to promote evaporation and to reduce air temperature against heat island phenomenon. Finally, we evaluated the relationship between the effect of groundwater use to ameliorate the heat island and the effect of infiltration on the water cycle in the catchment. These procedures to integrate the multi-scaled model simulation with political scenario based on the effective management of water resources as heat sink/source would be very powerful approaches to recovering a sound hydrologic cycle and create thermally-pleasing environments in the megalopolis. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Soil and vadose zone profiles are used as an archive of changes in groundwater recharge and water quality following changes in land use in an area of the Loess Plateau of China. A typical rain-fed loess-terrace agriculture region in Hequan, Guyuan is taken as an example and multiple tracers (chloride mass balance, stable isotopes, tritium, and water chemistry) are used to examine groundwater recharge mechanisms and to evaluate soil water chloride as an archive for recharge rate and water quality. Results show that groundwater recharge beneath natural uncultivated grassland, used as a baseline, is about 94–100 mm yr -1 and the time it takes for annual precipitation to reach water table through the thick unsaturated zone is from decades to hundreds of years (tritium free). This recharge rate is 2–3 orders of magnitude more than in the other semiarid areas with similar annual rainfall and with deep rooted vegetation and relatively high temperature. Most of the water that eventually becomes recharge originally infiltrated in the summer months. The conversion from native grassland to winter wheat has reduced groundwater recharge by 42–50% (50–55 mm yr -1 for recharge), and from winter wheat to alfalfa resulted in a significant chloride accumulation in the upper soil zone which terminated deep drainage. The paper also evaluates the time lag between potential recharge and actual recharge to aquifer and between increase in solute concentration in soil moisture and that in the aquifer following land-use change due to the deep unsaturated zone. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Shallow upland drains, grips, have been hypothesized as responsible for increased downstream flow magnitudes. Observations provide counterfactual evidence, often relating to the difficulty of inferring conclusions from statistical correlation and paired catchment comparisons; and the complexity of designing field experiments to test grip impacts at the catchment-scale. Drainage should provide drier antecedent moisture conditions, providing more storage at the start of an event; but, grips have higher flow velocities than overland flow so potentially delivering flow more rapidly to the drainage network. We develop and apply a model for assessing the impacts of grips upon flow hydrographs. The model was calibrated on the gripped case; then the gripped case was compared with the intact case by removing all grips. This comparison showed that even given parameter uncertainty, the intact case had significantly higher flood peaks and lower baseflows, mirroring field observations of the hydrological response of intact peat. The simulations suggest that this is because delivery effects may not to translate into catchment-scale impacts for three reasons. First, in our case, the proportions of flow path lengths that were hillslope were not changed significantly by gripping. Second, the structure of the grip network as compared with the structure of the drainage basin mitigated against grip-related increases in the concentration of runoff in the drainage network, although it did marginally reduce the mean timing of that concentration at the catchment outlet. Third, the effect of the latter upon downstream flow magnitudes can only be assessed by reference to the peak timing of other tributary basins, emphasizing that drain effects are both relative and scale dependent. However, given the importance of hillslope flow paths, we show that if upland drainage causes significant changes in surface roughness on hillslopes, then critical and important feedbacks may impact upon the speed of hydrological response. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Natural soil pipes are found in peatlands but little is known about their hydrological role. This paper presents the most complete set of pipe discharge data to date from a deep blanket peatland in northern England. In a 17.4-ha catchment, we identified 24 perennially-flowing and 60 ephemerally-flowing pipe outlets. Eight pipe outlets along with the catchment outlet were continuously gauged over an 18-month period. The pipes in the catchment were estimated to produce around 13.7 % of annual streamflow with individual pipes often producing large peak flows (maximum peak of 3.8 L s -1 ). Almost all pipes, whether ephemeral, perennially-flowing, shallow or deep (outlets 〉 1 m below the peat surface), showed increased discharge within a mean of 3 hours after rainfall commencement and were dominated by stormflow, indicating good connectivity between the peatland surface and the pipes. However, almost all pipes had a longer time period between hydrograph peak and return to baseflow compared to the stream (mean of 23.9 hours for pipes, 19.7 hours for stream). As a result, the proportion of streamflow produced by the pipes at any given time increased at low flows and formed the most important component of stream discharge for the lowest 10 % of flows. Thus, a small number of perennially-flowing pipes became more important to the stream system under low flow conditions and probably received water via matrix flow during periods between storms. Given the importance of pipes to streamflow in blanket peatlands, further research is required into their wider role in influencing stream-water chemistry, water temperature and fluvial carbon fluxes, as well as their role in altering local hydrochemical cycling within the peat mass itself. Enhanced piping within peatlands caused by environmental change may lead to changes in streamflow regime with larger low flows and more prolonged drainage of the peat. Copyright © 2012 John Wiley & Sons, Ltd.

Description: The hydrology of Quebec (Canada) boreal fens is poorly documented. Many peatlands are located in watersheds with impounded rivers. In such cases, their presence influences reservoir inflows. In recent years, some fens have been subjected to an increase of their wet area, a sign that they may be evolving towards an aquatic ecosystem. This dynamic process is referred to as aqualysis. This paper presents the seasonal and monthly hydrological budgets of a small watershed including a highly aqualysed fen (James Bay region). Monitoring of precipitation ( P ), runoff ( Q ) and groundwater levels ( WL ) was conducted during the ice-free season. Three semi-empirical equations (Thornthwaite, Priestley-Taylor and Penman-Monteith) were used and compared to calculate potential evapotranspiration ( PET ). The first two equations, having fewer parameters, estimate higher PET values than the third equation. The use of pressure level gauges installed in wells, for the calculation of peatland water storage, is inconclusive. Swelling of peat, peat decomposition and plant composition could be responsible for non-negligible amounts of absorbed water, which are not entirely accounted for by well levels. The estimation of peat matrix water storage is potentially the largest source of error and the limiting factor to calculate water balances in this environment. The results show that the groundwater level and the water storage vary depending on the season and especially after a heavy rainfall. Finally, the results illustrate the complexity of water routing through the site and, thus, raise several questions to be resolved in the future. Copyright © 2012 John Wiley & Sons, Ltd.

Description:    The nature of the gravity field inverse problem amplifies the noise in the GRACE data, which creeps into the mid and high degree and order harmonic coefficients of the Earth’s monthly gravity fields provided by GRACE. Due to the use of imperfect background models and data noise, these errors are manifested as north-south striping in the monthly global maps of equivalent water heights. In order to reduce these errors, this study investigates the use of the L-curve method with Tikhonov regularization. L-curve is a popular aid for determining a suitable value of the regularization parameter when solving linear discrete ill-posed problems using Tikhonov regularization. However, the computational effort required to determine the L-curve is prohibitively high for a large-scale problem like GRACE. This study implements a parameter-choice method, using Lanczos bidiagonalization which is a computationally inexpensive approximation to L-curve. Lanczos bidiagonalization is implemented with orthogonal transformation in a parallel computing environment and projects a large estimation problem on a problem of the size of about 2 orders of magnitude smaller for computing the regularization parameter. Errors in the GRACE solution time series have certain characteristics that vary depending on the ground track coverage of the solutions. These errors increase with increasing degree and order. In addition, certain resonant and near-resonant harmonic coefficients have higher errors as compared with the other coefficients. Using the knowledge of these characteristics, this study designs a regularization matrix that provides a constraint on the geopotential coefficients as a function of its degree and order. This regularization matrix is then used to compute the appropriate regularization parameter for each monthly solution. A 7-year time-series of the candidate regularized solutions (Mar 2003–Feb 2010) show markedly reduced error stripes compared with the unconstrained GRACE release 4 solutions (RL04) from the Center for Space Research (CSR). Post-fit residual analysis shows that the regularized solutions fit the data to within the noise level of GRACE. A time series of filtered hydrological model is used to confirm that signal attenuation for basins in the Total Runoff Integrating Pathways (TRIP) database over 320 km radii is less than 1 cm equivalent water height RMS, which is within the noise level of GRACE. Content Type Journal Article Category Original Article Pages 1-17 DOI 10.1007/s00190-012-0548-5 Authors Himanshu Save, Center for Space Research, The University of Texas at Austin, 3925 West Braker Lane, Suite 200, Austin, TX 78759-5321, USA Srinivas Bettadpur, Center for Space Research, The University of Texas at Austin, 3925 West Braker Lane, Suite 200, Austin, TX 78759-5321, USA Byron D. Tapley, Center for Space Research, The University of Texas at Austin, 3925 West Braker Lane, Suite 200, Austin, TX 78759-5321, USA Journal Journal of Geodesy Online ISSN 1432-1394 Print ISSN 0949-7714

Description:    In geopotential space, the fundamental geodetic parameter W 0 defines the Gauss–Listing geoid which can be used to best represent the Earth’s mean sea level (MSL) and hence specifies a conventional zero height level to unify vertical datums employed by mapping agencies throughout the world. Further, W 0 cannot be considered invariant as the parameter varies temporally as a direct response to sea level change and mass redistributions. This study determines W 0 and its rate, d W 0 /d t , by utilizing altimetric MSL models and an independent mean dynamic topography (MDT) model to define points on the geoid. W 0 and d W 0 /d t are estimated by two approaches: (i) by means of a global gravity field model (GGM) and (ii) within normal gravity field space as the geopotential value of the best fitting reference ellipsoid. The study shows that uncertainty in W 0 is mainly influenced by MDT while the choice of methodology, GGM and MSL data coverage are not significant within reason. Our estimate W 0 = 62636854.2 ± 0.2 m 2  s −2 at epoch 2005.0 differs by 1.8 m 2 s −2 from the International Astronomical Union reference value. This study shows that, at a sub-decadal time scale, the time variation d W 0 /d t stems mainly from sea level change with negligible effect from gravity field variations. d W 0 /d t = (−2.70 ± 0.03) × 10 −2  m 2  s −2  year −1 , corresponding to a MSL rise of 2.9 mm year −1 , is evaluated from sea level change based on 16 years of TOPEX and Jason-1 data. Content Type Journal Article Category Original Article Pages 1-14 DOI 10.1007/s00190-012-0547-6 Authors N. Dayoub, School of Civil Engineering and Geosciences, Newcastle University, Newcastle, NE1 7RU UK S. J. Edwards, School of Civil Engineering and Geosciences, Newcastle University, Newcastle, NE1 7RU UK P. Moore, School of Civil Engineering and Geosciences, Newcastle University, Newcastle, NE1 7RU UK Journal Journal of Geodesy Online ISSN 1432-1394 Print ISSN 0949-7714

Description: It is demonstrated that bed stiffnesses obtained by processing results of cyclic tests by the method of rapid Fourier transforms (WAK test) and numerical calculation, are rather approximate. Results of this investigation can be used for cyclic tests of a model in a centrifuge (during repeated loadings) for comparison with the (static) stiffness of the soil as determined from WAK-test data. Content Type Journal Article Category Earthquake-Resistant Construction Pages 1-6 DOI 10.1007/s11204-012-9157-9 Authors M. Parvizi, School of Engineering, University of Yasuj, Yasuj, Iran M. A. Qafari, School of Engineering, University of Yasuj, Yasuj, Iran Journal Soil Mechanics and Foundation Engineering Online ISSN 1573-9279 Print ISSN 0038-0741

Description:    Archaeomagnetism in Greece has continuously developed during the last decades. Numerous studies have provided high quality data and accurate secular variation curves for the direction and intensity of the geomagnetic field have been constructed. The Greek Secular Variation Curves (SVCs) cover the last 8 millennia for intensity and 6 millennia for direction. The coverage of the archaeological periods remains uneven, with several gaps, mostly in the directional dataset, with only two results for periods older than 2500 B.C. In the present contribution, the first archaeomagnetic results from Neolithic settlements in northern Greece are presented. For the present study, samples were collected from three different archaeological sites: burnt structures in Avgi (Kastoria) and Vasili (Farsala) and one oven from Sosandra (Aridaia). The natural remanent magnetization (NRM) grouping of all specimens indicated that the majority of the samples were burnt in situ, providing thus a reliable direction of the ancient field. Magnetic cleaning (both alternating-field and thermal) revealed the presence of one stable component of magnetisation. Rock magnetic experiments (acquisition of isothermal remanent magnetization (IRM), thermal demagnetisation of the IRM, thermomagnetic curves) have been performed on pilot samples indicating that low coercivity magnetic minerals such as magnetite or Timagnetite are prevailing. The mean directions (declination D, inclination I and parameters of the Fisherian statistics), which arose from the three sites are as follows: Sosandra: D = 343°, I = 55.6°, α 95 = 4.8°; Avgi: D = 10.1°, I = 53.4°, α 95 = 4.2° and Vasili: D = 357.5°, I = 43.1°, α 95 = 4.1°. The obtained data are in a very good agreement with results from Neolithic Bulgaria. This study represents the beginning of an effort to fill the gaps of the Greek secular variation curves and their extension to the Neolithic period. Content Type Journal Article Pages 1-18 DOI 10.1007/s11200-011-9006-8 Authors Elina Aidona, Department of Geophysics, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece Despina Kondopoulou, Department of Geophysics, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece Journal Studia Geophysica et Geodaetica Online ISSN 1573-1626 Print ISSN 0039-3169

Description:    The quality of harvested rainwater used for toilet flushing in a private house in the south-west of France was assessed over a one-year period. Twenty-one physicochemical parameters were screened using standard analytical techniques. The microbiological quality of stored roof runoff was also investigated and total flora at 22°C and 36°C, total coliforms, Escherichia Coli , enteroccocci, Cryptospridium oocysts, Giardia cysts, Legionella species , Legionella pneumophila , Aeromonas , and Pseudomonas aeruginosa were analysed. Chemical and microbiological parameters fluctuated during the course of the study, with the highest levels of microbiological contamination observed in roof runoffs collected during the summer. Overall, the collected rainwater had a relatively good physicochemical quality but variable, and, did not meet the requirements for drinking water and a microbiological contamination of the water was observed. The water balance of a 4-people standard family rainwater harvesting system was also calculated in this case study. The following parameters were calculated: rainfall, toilets flushing demand, mains water, rainwater used and water saving efficiency. The experimental water saving efficiency was calculated as 87%. The collection of rainwater from roofs, its storage and subsequent use for toilet flushing can save 42 m 3 of potable water per year for the studied system. Content Type Journal Article Pages 1-9 DOI 10.1007/s11269-012-0012-6 Authors C. Vialle, INRA; Université de Toulouse; INP; LCA (Laboratoire de Chimie Agro-Industrielle); ENSIACET, 4 Allées Emile Monso, 31029 Toulouse, France C. Sablayrolles, INRA; Université de Toulouse; INP; LCA (Laboratoire de Chimie Agro-Industrielle); ENSIACET, 4 Allées Emile Monso, 31029 Toulouse, France M. Lovera, Veolia Water North America, Technical Direction Group, 101, W Washington Street, Suite 1440 East, IN-46204 Indianapolis, USA M.-C. Huau, Veolia Eau, 36-38 avenue Kleber, 75016 Paris, France S. Jacob, Veolia Eau, Direction Technique, Immeuble Giovanni Battista B, 1, rue Giovanni Battista Pirelli, 94410 Saint Maurice, France M. Montrejaud-Vignoles, INRA; Université de Toulouse; INP; LCA (Laboratoire de Chimie Agro-Industrielle); ENSIACET, 4 Allées Emile Monso, 31029 Toulouse, France Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    Urban stormwater quality is multifaceted and the use of a limited number of factors to represent catchment characteristics may not be adequate to explain the complexity of water quality response to a rainfall event or site-to-site differences in stormwater quality modelling. This paper presents the outcomes of a research study which investigated the adequacy of using land use and impervious area fraction only, to represent catchment characteristics in urban stormwater quality modelling. The research outcomes confirmed the inadequacy of the use of these two parameters alone to represent urban catchment characteristics in stormwater quality prediction. Urban form also needs to be taken into consideration as it was found have an important impact on stormwater quality by influencing pollutant generation, build-up and wash-off. Urban form refers to characteristics related to an urban development such as road layout, spatial distribution of urban areas and urban design features. Content Type Journal Article Pages 1-7 DOI 10.1007/s11269-012-0014-4 Authors An Liu, School of Urban Development, Queensland University of Technology, GPO Box 2434, Brisbane, QLD 4000, Australia Ashantha Goonetilleke, School of Urban Development, Queensland University of Technology, GPO Box 2434, Brisbane, QLD 4000, Australia Prasanna Egodawatta, School of Urban Development, Queensland University of Technology, GPO Box 2434, Brisbane, QLD 4000, Australia Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    Gravity data observed on or reduced to the ellipsoid are preferably represented using ellipsoidal harmonics instead of spherical harmonics. Ellipsoidal harmonics, however, are difficult to use in practice because the computation of the associated Legendre functions of the second kind that occur in the ellipsoidal harmonic expansions is not straightforward. Jekeli’s renormalization simplifies the computation of the associated Legendre functions. We extended the direct computation of these functions—as well as that of their ratio—up to the second derivatives and minimized the number of required recurrences by a suitable hypergeometric transformation. Compared with the original Jekeli’s renormalization the associated Legendre differential equation is fulfilled up to much higher degrees and orders for our optimized recurrences. The derived functions were tested by comparing functionals of the gravitational potential computed with both ellipsoidal and spherical harmonic syntheses. As an input, the high resolution global gravity field model EGM2008 was used. The relative agreement we found between the results of ellipsoidal and spherical syntheses is 10 −14 , 10 −12 and 10 −8 for the potential and its first and second derivatives, respectively. Using the original renormalization, this agreement is 10 −12 , 10 −8 and 10 −5 , respectively. In addition, our optimized recurrences require less computation time as the number of required terms for the hypergeometric functions is less. Content Type Journal Article Category Original Article Pages 1-14 DOI 10.1007/s00190-012-0549-4 Authors Josef Sebera, Faculty of Civil Engineering, CTU in Prague, Thákurova 7, 166 29 Praha 6, Czech Republic Johannes Bouman, Deutsches Geodätisches Forschungsinstitut, Alfons-Goppel-Strasse 11, 80539 München, Germany Wolfgang Bosch, Deutsches Geodätisches Forschungsinstitut, Alfons-Goppel-Strasse 11, 80539 München, Germany Journal Journal of Geodesy Online ISSN 1432-1394 Print ISSN 0949-7714

Description:    The paper presents modified Lin and Wang’s and Hedgley’s algorithms to tackle the problem of transforming Cartesian to geodetic coordinates on a triaxial ellipsoid. Originally, the methods were developed for an ellipsoid of revolution but due to their universality, they may be adapted to the more complicated problem stated on a triaxial ellipsoid what is in fact done in this work. Two modified methods are compared to the vector method recently introduced by Feltens. The modified methods turn out to be more accurate and faster than the algorithm presented by Feltens. Content Type Journal Article Pages 1-14 DOI 10.1007/s11200-011-9017-5 Authors Marcin Ligas, Department of Geomatics, AGH University of Science and Technology, Krakow, Poland Journal Studia Geophysica et Geodaetica Online ISSN 1573-1626 Print ISSN 0039-3169

Description: Potential climate change effects on aspects of conjunctive management of water resources can be evaluated by linking climate models with fully integrated groundwater–surface water models. The objective of this study is to develop a modeling system that links global climate models with regional hydrologic models, using the California Central Valley as a case study. The new method is a supply and demand modeling framework that can be used to simulate and analyze potential climate change and conjunctive use. Supply-constrained and demand-driven linkages in the water system in the Central Valley are represented with the linked climate models, precipitation-runoff models, agricultural and native vegetation water use, and hydrologic flow models to demonstrate the feasibility of this method. Simulated precipitation and temperature were used from the GFDL-A2 climate change scenario through the 21st century to drive a regional water balance mountain hydrologic watershed model (MHWM) for the surrounding watersheds in combination with a regional integrated hydrologic model of the Central Valley (CVHM). Application of this method demonstrates the potential transition from predominantly surface water to groundwater supply for agriculture with secondary effects that may limit this transition of conjunctive use. The particular scenario considered includes intermittent climatic droughts in the first half of the 21st century followed by severe persistent droughts in the second half of the 21st century. These climatic droughts do not yield a valley-wide operational drought but do cause reduced surface water deliveries and increased groundwater abstractions that may cause additional land subsidence, reduced water for riparian habitat, or changes in flows at the Sacramento–San Joaquin River Delta. The method developed here can be used to explore conjunctive use adaptation options and hydrologic risk assessments in regional hydrologic systems throughout the world.

Description:    The present study was carried out with the objective of determining the extent of groundwater pollution caused by tanning industries in Chromepet area located south of Chennai, Tamil Nadu, India. Groundwater samples were collected during January and March 2008 from 36 wells and were analysed for the concentration of various major ions and chromium. Na-Cl was the dominant water type found in this area. Groundwater in this area is not suitable for drinking as it contains elevated concentration of most major ions and chromium. This is due to the recharge of partially treated effluent discharged by tanning industries into open drains. The concentration of chromium was above the permissible limit (0.05 mg/l) in 86% of the groundwater samples. The use of chemicals, such as sodium chloride, sodium sulphate, chromium sulphate etc. during the tanning processes is the major reason for the high concentration of major ions and chromium in groundwater. Hence it is important to regulate the industries and also take measures to reduce the total dissolved solids in the treated effluent before disposal. The groundwater quality of this region can also be improved by adopting rainwater harvesting thereby increasing groundwater recharge. Content Type Journal Article Pages 1-15 DOI 10.1007/s11269-012-9985-4 Authors K. Brindha, Department of Geology, Anna University, Chennai, Tamil Nadu, India L. Elango, Department of Geology, Anna University, Chennai, Tamil Nadu, India Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    The Agua Amarga coastal aquifer, located in the southeast of Spain (Alicante province) has suffered a significant decrease in its piezometric levels due to its use to supply water to Alicante I and II desalination plants. In order to recover its natural levels and to preserve the salt marsh of ecological interest linked to the aquifer, whose origin is related to ancient saltworks, a pilot scheme based on depositing seawater over the salt marsh surface has been carried out from December 2009 to July 2010. As a result, piezometric levels have increased by around 2 and 3 m below the salt marsh and a general decrease in groundwater salinity of between 15 and 100 g/l has been measured. A flow-transport numerical model with SEAWAT is used to assess and evaluate the seawater depositing programme. Content Type Journal Article Pages 1-15 DOI 10.1007/s11269-012-9987-2 Authors I. Alhama Manteca, Departamento Ingeniería Minera, Geológica y Cartográfica, UPCT, Cartagena, Spain T. Rodríguez Estrella, Departamento Ingeniería Minera, Geológica y Cartográfica, UPCT, Cartagena, Spain F. Alhama, Departamento Física Aplicada, UPCT, Cartagena, Spain Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    Groundwater is a valuable resource for irrigation water. The use of groundwater for irrigation depends on environmental factors affecting long term sustainability and the costs of extraction which affect the economic viability. The cost of extraction depends upon the depth of drilling required and the rates of groundwater extraction that can be achieved. This is determined by the natural water flow through aquifers and so requires an estimation of hydraulic conductivity (K). In the irrigated area of Pakistan the Geoelectrical method, Vertical Electrical Sounding (VES) was tested to estimate aquifer hydraulic conductivity. A resistivity meter was used to collect VES data by employing a Schlumberger electrode configuration, with half current electrode spacings (AB/2) ranging from 2 to 180 m and the potential electrode (MN) from 1 to 40 m. The field data were interpreted using the Interpex IX1D computer software and the aquifer resistivity (ρ) vs depth models for each location were estimated. A total of 102 groundwater samples from nearby hydrowells at different depths were also collected for Electrical Conductivity (EC) to measure groundwater resistivities (ρ o ). The resultant formation factor (F=ρ/ρ o ) values varied between 0.79 and 12.32 for the entire study area. The extreme values of F obtained from the VES surveys were paired with extreme values of K derived from field tests to provide a linear model of F:K. Seven pumping tests were also carried out to determine K and test the F:K correlation. The empirical relationship developed between the formation factors was highly significant and as such can be helpful for the estimation of hydraulic conductivity for groundwater pumping investigations in this area. This approach to deriving a relationship between the formation factor and hydraulic conductivity can be useful for groundwater investigations elsewhere. Content Type Journal Article Pages 1-15 DOI 10.1007/s11269-011-9954-3 Authors P. Sikandar, CSIRO, Land and Water, 2680 Griffith, NSW, Australia E. W. Christen, Griffith laboratory, CSIRO Land and Water & Sustainable Agriculture Flagship, Griffith, NSW 2680, Australia Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    Prediction of mixing intensity of water masses in riverine Lake Tegel (Berlin, Germany) can be used to trace the fate of pollutants that enter the lake through several inflows. Because the contributions of each inflow have not yet been quantified and because the lake features complex bathymetry and numerous islands, a hydrodynamic circulation model with high spatial resolution and dynamic wind forcing is useful. We applied the two-dimensional version of the Princeton Ocean Model to separate the influences of wind and river discharge on the currents and mass transport in Lake Tegel. For model validation, we compared the simulation results with 1 year of electrical conductivity data, which was used as a conservative tracer to distinguish between water from the River Havel and water supplied by a smaller second inflow. Calculation of currents alone is insufficient to investigate water exchanges between rivers and lakes, especially when several islands create multiple pathways for river intrusion. Therefore, mass transport simulations are applied. Our calculations based on archetypical scenarios indicate that the proportion of (polluted) water from the River Havel in the main basin of Lake Tegel fluctuates with river discharge and wind, which either amplify or neutralize each other. Content Type Journal Article Category Original Article Pages 1-19 DOI 10.1007/s10652-012-9236-5 Authors Sebastian Schimmelpfennig, Department of Ecohydrology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany Georgiy Kirillin, Department of Ecohydrology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany Christof Engelhardt, Department of Ecohydrology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany Gunnar Nützmann, Department of Ecohydrology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany Journal Environmental Fluid Mechanics Online ISSN 1573-1510 Print ISSN 1567-7419

Description: Erratum to: Mission design, operation and exploitation of the Gravity field and steady-state Ocean Circulation Explorer (GOCE) mission Content Type Journal Article Category Erratum Pages 1-1 DOI 10.1007/s00190-012-0541-z Authors Rune Floberghagen, Earth Observation Programmes, European Space Agency, Frascati, Italy Michael Fehringer, Earth Observation Programmes, European Space Agency, Frascati, Italy Daniel Lamarre, Earth Observation Programmes, European Space Agency, Frascati, Italy Danilo Muzi, Earth Observation Programmes, European Space Agency, Frascati, Italy Björn Frommknecht, Earth Observation Programmes, European Space Agency, Frascati, Italy Christoph Steiger, Human Spaceflight and Operations, European Space Agency, Darmstadt, Germany Juan Piñeiro, Human Spaceflight and Operations, European Space Agency, Darmstadt, Germany Andrea da Costa, Human Spaceflight and Operations, European Space Agency, Darmstadt, Germany Journal Journal of Geodesy Online ISSN 1432-1394 Print ISSN 0949-7714

Description: An efficient approach is developed to analytically evaluate solute transport in a horizontal, divergent radial flow field with a multistep injection flow rate and an arbitrary input concentration history. By assuming a piecewise steady state flow and transforming the time domain to the cumulative injected flow domain, the concentration distribution is found to be completely determined by the total volume of injected flow and independent of specific flow rates. Thus, on the cumulative flow domain, the transport problem with a temporally varying velocity field can be transformed into a steady state flow problem. Linear convolution can then be applied on the cumulative injected flow domain to evaluate the solution for an arbitrarily time-dependent input concentration. Solutions on the regular time domain can be conveniently obtained by mapping the solution on the cumulative injected flow domain to the time domain. Furthermore, we theoretically examine the conditions for the assumption of piecewise steady state flow to be valid. On the basis of the critical time scale of the “pseudosteady state condition,” defined as when velocity changes accomplish 99% of their steady state differences, and the relative error in the mean travel time of plume front, we obtain conditions for neglecting the transitional period between two pumping steps. Such conditions include the following: (1) the duration of a pumping step, tp, must be longer than the critical time scale, tc, i.e., tp ≥ tc = 25r2S/T, where r is the radial distance, S is the storage coefficient, and T is the transmissivity, or similarly, a maximum problem domain needs to be defined for a given pumping strategy. (2) the maximum well pumping rate, qmax, should satisfy qmax ≤ πθT/25S, where θ is the effective porosity. When both conditions are satisfied, transitional periods may be neglected.

Description: Meander bends in alluvial rivers morphologically evolve toward meander cutoff with narrowing intra-meander necks, and this should steepen hydraulic gradients and intensify intra-meander hyporheic flux. This research used dye tracking and head loss measurements in a 1:500 planimetrically scaled laboratory river table to quantify the spatial and temporal intensification of intra-meander flux rates at two evolution ages. The younger meander bend, M1, had a sinuosity of 2.3, a river neck width of 0.39 cm, and 0.6% river slope, and the older meander bend, M3, had a sinuosity of 5.2, a river neck width of 0.12 cm, and 0.5% river slope. Flux into and out of the meander bend was estimated along the normalized curvilinear distance s *, with the meander neck at s * = 0.1 and s * = 0.9, the meander centroid at s * = 0.37 and s * = 0.63, and the apex at s * = 0.5. Between the meander centroid and neck we documented a 60% spatial intensification for M1 and a 90% spatial intensification for M3. Between M1 and M3 we documented a 135% temporal intensification at the neck and a 100% intensification at the centroid. Our empirical spatial and temporal intensification rates involving the M1 and the M3 scenario were 1 to 3 times lower than theoretical rates derived from a river evolution model with equivalent M1 and M3 planimetry. Over estimation by the theoretical model was attributed to exaggerated head loss caused by the model neglecting groundwater contributions to river stage. Hyporheic exchange provides critical ecosystem services and its spatial and temporal variation with meander evolution should be considered in river management. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Watershed models which combine hydrology and water quality are being widely utilized in integrated watershed management for the determination of best water management practices. In this study, the hydrology of the Lower Porsuk Stream Watershed in Turkey has been modeled with SWAT to determine optimal water management strategies. The calibration and validation process have been accomplished using data from two monitoring stations. The model has been run for the 1978–2009 period and while the 1998–2004 period has been used for calibration, the validation has spanned the whole period. The SWATCup calibration and uncertainity program has been utilized for this purpose. No significant differences have been detected among different iteration numbers in the calibration period. The monthly Nash-Sutcliffe and R 2 performance indicatiors for the upstream Esenkara station have been 0.74 and 0.88, respectively for the calibration period, and 0.87 and 0.87, respectively for the validation period. The Kıranharmanı station which is located close to the watershed outlet has shown values of 0.59 and 0.72, respectively for the calibration period, and 0.44 and 0.56, respectively for the validation period. There are uncertanities in the abstracted irrigation and groundwater quantities which have reflected in the results in the Kıranharmanı station which is more affected as it lies downstream of the irrigation areas. The effects of different irrigation practices on the flow regime have been also investigated. A scenario has been implemented in which drip irrigation wholly replaces conventional furrow and sprinkler irrigation. The scenario has shown increases in stream flows by 87 % for the whole year. The adoption of more efficient irrigation practices thus results in reducing the water stress induced by irrigation demands. With this study a modeling framework has been founded to aid water management applications in the Lower Porsuk Stream Watershed by generating scenarios for best management practices. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Many observations and studies have shown that water resources amount in the Hai River Basin decreased significantly over the last half of the twentieth century. This study attempts to attribute the observed changes in the water resources amount in the basin over a 40 year period (1961–2000) to different factors, including natural climate variability, climate change induced by anthropogenic forcing of greenhouse gas emissions (referred to as anthropogenic forcing hereafter), and local human activity. First, the temporal variation of the annual water resources amount in the basin during the past 40 years is analyzed by employing the moving-average method, the linear regression method, and the Mann-Kendall method. Second, through setting different scenarios, the effects on the water resources amount due to different factors, including natural climate variability, anthropogenic forcing, and local human activity, are obtained using the parallel climate model, the distributed hydrological model water and energy transfer processes in large river basins, and the statistical downscaling model. Third, the fingerprint-based attribution method is used to obtain the signal strengths of observed changes in water resources amount during 1961–2000 and changes in the water resources amount under different scenarios. Finally, by comparing the signal strengths, the observed changes in water resources amount in the basin can be attributed to different factors. The results indicate that natural climate variability and local human activity may be two factors responsible for the observed changes in the water resources amount during the past 40 years in the basin, with local human activity being the main factor and accounting for about 60% of the changes.

Description:    This work discusses the conflict between two of the main objectives of the EU Water Framework Directive: cost recovery and economic efficiency in the use of irrigation water. In the Mediterranean region, this conflict is commonly embedded in a state of under-utilization of irrigation networks managed by Water User Associations (WUAs). This under-utilization arises from factors independent of farmers’ choice, such as water shortage, crises in the sector, and changes to the Common Agricultural Policy. This prevents the facilities from operating at the minimum average cost. This paper argues that farmers should not suffer this inefficiency, which results in them paying higher water prices to cover the costs of water supply. Indeed, the application of the Water Directive should be rethought, taking into account the specific problems related to irrigation in the Mediterranean region. Based on an econometric analysis of the costs of water distribution in a WUA in Sardinia (Italy), we propose a payment system based on two components. Primarily there is a fee related to the number of hectares under irrigation. In addition there is a fee that considers the intensity of irrigation: this component is to encourage farmers to save water. The results show that the proposed approach has some desirable effects, including higher rates of cost recovery and possibly a reduction in the use of groundwater. Finally, the proposed system is not overly expensive for the rest of the community, who must bear the costs of inefficiencies in the use of irrigation water that do not depend on choices of farmers. Content Type Journal Article Pages 1-13 DOI 10.1007/s11269-012-9991-6 Authors Gabriele Dono, University of Tuscia, Viterbo, Italy Luca Giraldo, University of Tuscia, Viterbo, Italy Simone Severini, University of Tuscia, Viterbo, Italy Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description: Flood events can induce temporal changes in streambed elevation and particle-size composition, which may influence the bed's hydraulic properties and stream-aquifer fluxes during and after an event. This study combines a set of previously developed modeling approaches to create a synthetic flood event during which bed sediment is entrained and deposited as a function of hydraulic conditions and particle size. One simulated river reach in a state of approximate dynamic equilibrium is chosen to investigate the impacts of size-selective sediment transport on stream-aquifer interaction. Along this reach, the preferential entrainment of fine sediment during the flood's rising limb leads to overall bed coarsening, and increases in vertical hydraulic conductivity (Kbv) and downward fluxes of floodwater into the streambed. Progressively finer sediment layers are deposited during the event's falling limb, causing the redevelopment of a colmation (clogging) layer on the bed surface and a decline in overall Kbv by the event's conclusion. This reduction in Kbv leads to prolonged retention of event water in the streambed (after the reach reverts from losing to gaining river conditions) when compared with what is expected if pre-event Kbv values are used to estimate river-aquifer exchanges. This process of sequential bed coarsening and fining during a flood event provides a mechanistic explanation for the event size-and-duration threshold, inferred in some systems, that must be exceeded for significant amounts of flood recharge to occur. The major consequences of these processes—enhanced infiltration and prolonged floodwater retention—have potentially major implications for groundwater-surface water interactions, water quality, contaminant transport, and riparian biogeochemistry.

Description: Nonstationary oscillation (NSO) processes are observed in a number of hydroclimatic data series. Stochastic simulation models are useful to study the impacts of the climatic variations induced by NSO processes into hydroclimatic regimes. Reproducing NSO processes in a stochastic time series model is, however, a difficult task because of the complexity of the nonstationary behaviors. In the current study, a novel stochastic simulation technique that reproduces the NSO processes embedded in hydroclimatic data series is presented. The proposed model reproduces NSO processes by utilizing empirical mode decomposition (EMD) and nonparametric simulation techniques (i.e., k-nearest-neighbor resampling and block bootstrapping). The model was first tested with synthetic data sets from trigonometric functions and the Rössler system. The North Atlantic Oscillation (NAO) index was then examined as a real case study. This NAO index was then employed as an exogenous variable for the stochastic simulation of streamflows at the Romaine River in the province of Quebec, Canada. The results of the application to the synthetic data sets and the real-world case studies indicate that the proposed model preserves well the NSO processes along with the key statistical characteristics of the observations. It was concluded that the proposed model possesses a reasonable simulation capacity and a high potential as a stochastic model, especially for hydroclimatic data sets that embed NSO processes.

Description: Vegetation zonation and tidal hydrology are basic attributes of intertidal salt marshes, but specific links among vegetation zonation, plant water use, and spatiotemporally dynamic hydrology have eluded thorough characterization. We developed a quantitative model of an intensively studied salt marsh field site, integrating coupled 2-D surface water and 3-D groundwater flow and zonal plant water use. Comparison of model scenarios with and without heterogeneity in (1) evapotranspiration rates and rooting depths, according to mapped vegetation zonation, and (2) sediment hydraulic properties from inferred geological heterogeneity revealed the coupled importance of both sources of ecohydrological variability at the site. Complex spatial variations in root zone pressure heads, saturations, and vertical groundwater velocities emerged in the model but only when both sources of ecohydrological variability were represented together and with tidal dynamics. These regions of distinctive root zone hydraulic conditions, caused by the intersection of vegetation and sediment spatial patterns, were termed “ecohydrological zones” (EHZ). Five EHZ emerged from different combinations of sediment hydraulic properties and evapotranspiration rates, and two EHZ emerged from local topography. Simulated pressure heads and groundwater dynamics among the EHZ were validated with field data. The model and data showed that hydraulic differences between EHZ were masked shortly after a flooding tide but again became prominent during prolonged marsh exposure. We suggest that ecohydrological zones, which reflect the combined influences of topographic, sediment, and vegetation heterogeneity and do not emphasize one influence over the others, are the fundamental spatial habitat units comprising the salt marsh ecosystem.

Description:    Estimation of crop variables is necessary for crop type monitoring as well as crop yield forecast. At the present era artificial neural network methodology are widely used to the remote sensing domain for numerous applications like crop yield forecasting and crop type classification. In the present work, two neural network models namely general regression neural network (GRNN) and radial basis function neural network (RBFNN) are used to estimate crop variables: leaf area index (LAI), biomass (BM), plant height (PH) and soil moisture (SM) by using ground based X-band scatterometer data. The both networks are trained and tested with X-band scatterometer data. The performance of the GRNN and RBFNN networks are found that the radial basis approach is more suitable for crop variable estimation in comparison to the GRNN approach. This work presents the applicability of neural network as an estimator and method employed could be useful to estimate the crop variables of other crops. Content Type Journal Article Category Short Note Pages 1-7 DOI 10.1007/s12524-011-0197-9 Authors Abhishek Pandey, Department of Applied Physics, Institute of Technology, Banaras Hindu University, Varanasi, 221005 India Khem B. Thapa, Department of Physics, University Institute of Engineering and Technology, CSJM University, Kanpur, 208024 India R. Prasad, Department of Applied Physics, Institute of Technology, Banaras Hindu University, Varanasi, 221005 India K. P. Singh, Department of Electronics Engineering, Institute of Technology, Banaras Hindu University, Varanasi, 221005 India Journal Journal of the Indian Society of Remote Sensing Online ISSN 0974-3006 Print ISSN 0255-660X

Description: Quantification of biophysical parameters of urban trees is important for urban planning, and for assessing carbon sequestration and ecosystem services. Airborne lidar has been used extensively in recent years to estimate biophysical parameters of trees in forested ecosystems. However, similar studies are largely lacking for individual trees in urban landscapes. Prediction models to estimate biophysical parameters such as height, crown area, diameter at breast height, and biomass for over two thousand individual trees were developed using best subsets multiple linear regression for a study area in central Oklahoma, USA using point cloud distributional metrics from an Optech ALTM 2050 lidar system. A high level of accuracy was attained for estimating individual tree height (R2 = 0.89), dbh (R2 = 0.82), crown diameter (R2 = 0.90), and biomass (R2 = 0.67) using lidar-based metrics for pooled data of all tree species. More variance was explained in species-specific estimates of biomass (R2 = 0.68 for Juniperus virginiana to 0.84 for Ulmus parviflora) than in estimates from broadleaf deciduous (R2 = 0.63) and coniferous (R2 = 0.45) taxonomic groups—or the data set analysed as a whole (R2 = 0.67). The metric crown area performed particularly well for most of the species-specific biomass equations, which suggests that tree crowns should be delineated accurately, whether manually or using automatic individual tree detection algorithms, to obtain a good estimation of biomass using lidar-based metrics.

Description: In recent decades, copula functions have been applied in bivariate drought duration and severity frequency analysis. Among a number of potential copulas, Clayton has been mostly employed in drought analysis. In this research, we study the influence of the tail shape of various copula functions (i.e. Gumbel, Frank, Clayton, and Gaussian) on drought bivariate frequency analysis. The appropriateness of Clayton copula for the characterization of drought characteristics is also investigated. Drought data are extracted from standardized precipitation index (SPI) time series for four stations in Canada (La Tuque and Grande Prairie) and Iran (Anzali and Zahedan). Both duration and severity datasets are positively skewed. Different marginal distributions were first fitted to drought duration and severity data. The gamma and exponential distributions were respectively selected for drought duration and severity according to the positive skewness and Kolmogorov- Smirnov test. The results of copula modeling show that the Clayton copula function is not an appropriate choice for the employed datasets in the current study, and does not give more drought risk information than an independent model for which the duration and severity dependence is not significant. The reason is that the dependence of two variables in the upper tail of Clayton copula is very weak and similar to the independent case, while the observed data in the transformed domain of cumulative density function shows high association in the upper tail. Instead, the Frank and Gumbel copula functions show better performance than Clayton function for drought bivariate frequency analysis. Copyright © 2012 John Wiley & Sons, Ltd.

Description: Soil hydraulic parameters were upscaled from a 30 m resolution to a 1 km resolution using a new aggregation scheme (described in the companion paper) where the scale parameter was based on the topography. When soil hydraulic parameter aggregation or upscaling schemes ignore the effect of topography, their application becomes limited at hillslope scales and beyond, where topography plays a dominant role in soil deposition and formation. Hence the new upscaling algorithm was tested at the hillslope scale (1 km) across two locations: (1) the Little Washita watershed in Oklahoma, and (2) the Walnut Creek watershed in Iowa. The watersheds were divided into pixels of 1 km resolution and the effective soil hydraulic parameters obtained for each pixel. Each pixel/domain was then simulated using the physically based HYDRUS-3-D modeling platform. In order to account for the surface (runoff/on) and subsurface fluxes between pixels, an algorithm to route infiltration-excess runoff onto downstream pixels at daily time steps and to update the soil moisture states of the downstream pixels was applied. Simulated soil moisture states were compared across scales, and the coarse scale values compared against the airborne soil moisture data products obtained during the hydrology experiment field campaign periods (SGP97 and SMEX02) for selected pixels with different topographic complexities, soil distributions, and land cover. Results from these comparisons show good correlations between simulated and observed soil moisture states across time, topographic variations, location, elevation, and land cover. Stream discharge comparisons made at two gauging stations in the Little Washita watershed also provide reasonably good results as to the suitability of the upscaling algorithm used. Based only on the topography of the domain, the new upscaling algorithm was able to provide coarse resolution values for soil hydraulic parameters which effectively captured the variations in soil moisture across the watershed domains.

Description: Hydropower accounts for about 20% of the worldwide electrical power production. In mountainous regions this ratio is significantly higher. In this study we present how future projected climatic forcing, as described in regional climate models (RCMs), will affect water resources and subsequently hydropower production in downstream hydropower plants in a glacierized alpine valley (Vispa valley, Switzerland, 778 km2). In order to estimate future runoff generation and hydropower production, we used error-corrected and downscaled climate scenarios from regional climate models (RCMs) as well as glacier retreat projections from a dynamic glacier model and coupled them to a physically based hydrological model. Furthermore, we implemented all relevant hydropower operational rules in the hydrological model to estimate future hydropower production based on the runoff projections. The uncertainty of each modeling component (climate projections, glacier retreat, and hydrological projection) and the resulting propagation of uncertainty to the projected future water availability for energy production were assessed using an analysis of variance. While the uncertainty of the projections is considerable, the consistent trends observed in all projections indicate significant changes to the current situation. The model results indicate that future melt- and rainfall-runoff will increase during spring but decline during summer. The study concludes by outlining the most relevant expected changes for hydropower operations.

Description: The effect of spatial concentration fluctuations on the reaction of two solutes, A + B ⇀ C, is considered. In the absence of fluctuations, the concentration of solutes decays as Adet = Bdet ∼ t−1. Contrary to this, experimental and numerical studies suggest that concentrations decay significantly slower. Existing theory suggests a t−d/4 scaling in the asymptotic regime (d is the dimensionality of the problem). Here we study the effect of fluctuations using the classical diffusion-reaction equation with random initial conditions. Initial concentrations of the reactants are treated as correlated random fields. We use the method of moment equations to solve the resulting stochastic diffusion-reaction equation and obtain a solution for the average concentrations that deviates from ∼t−1 to ∼t−d/4 behavior at characteristic transition time t*. We also derive analytical expressions for t* as a function of Damköhler number and the coefficient of variation of the initial concentration.

Description: Based on existing techniques in nonlinear physics that work in the Fourier domain, we develop a multivariate, wavelet-based method for the generation of synthetic discharge time series. This approach not only retains the cross-correlative structure of the original data (which makes it preferable to principal component methods that merely preserve the correlations) but also replicates the nonlinear properties of the original data. We argue that the temporal asymmetry of the typical hydrograph is the most important form of nonlinearity to preserve in the synthetic data. Using the derivative skewness as a measure of asymmetry and an example data set of 35 years of daily discharge data from 107 gauging stations in the United States, we compare two approaches that preserve the asymmetry of the original records. We generate synthetic data and then study the properties of fitting a generalized extreme value distribution to the annual maxima for a total flux time series. The synthetic series provides error bands for the fitted distribution that give a different way of assessing credible return periods. It is found that the best approach for studying extremes is to match the asymmetry of each series individually, rather than to formulate a global threshold criterion.

Description: This article focuses on household water use in Spain by analyzing the influence of a detailed set of factors. We find that, although the presence of both water-saving equipment and water-conservation habits leads to water savings, the factors that influence each are not the same. In particular, our results show that those individuals most committed to the adoption of water-saving equipment and, at the same time, less committed to water-conservation habits tend to have higher incomes.

Description: Wetlands are valuable ecosystems that provide many valuable services, yet many of these important ecosystems are at risk because of current trends in climate change. The Prairie Pothole Region (PPR) in the upper-midwest of the U.S. and south-central Canada, characterized by glacially-sculpted landscapes and abundant wetlands, is one such vulnerable region. According to regional/global climate model predictions, drought occurrence will increase in the PPR region through the 21st century and thus will probably cause the amount of water in wetlands to decline. Water surface area (WSA) of Kidder County, ND from 1984-2011 was measured by classifying TM/ETM+ images through the Modified Normalized Difference Water Index (MNDWI).We then developed a linear model based on the water surface area (WSA) of these wetlands and historical climate data, and used this to determine the wetland sensitivity to climate change and predict future wetlands WSA in the PPR. Our model based on Palmer Drought Severity Index (PDSI) of the current year (PDSI t-0 ) and two years previous (PDSI t-2 ) can explain 79% of the annual wetland WSA variance, suggesting a high sensitivity of wetlands to drought/climate change. We also predicted the PPR wetlands WSA in the 21st century under A1B scenario (a mid-carbon emission scenario) using simulated PDSI based on IPCC AR4 22-model ensemble climate. According to our prediction, the WSA of the PPR wetlands will decrease to less than half of the baseline WSA (defined as the mean wetlands WSA of the 2000s) by the mid of the 21st century, and to less than one-third by the 2080s, and will then slightly increase in the 2090s. This considerable future wetland loss caused only by climate change provides important implication to future wetland management and climate adaptation policy. Copyright © 2012 John Wiley & Sons, Ltd.

Description: In hydrology, the storage-discharge relationship is a fundamental catchment property. Understanding what controls this relationship is at the core of catchment science. To date, there are no direct methods to measure water storage at catchment scales (10 1 -10 3  km 2 ). In this study, we use direct measurements of terrestrial water storage dynamics by means of superconducting gravimetry in a small headwater catchment of the Regen River, Germany, to derive empirical storage-discharge relationships in nested catchments of increasing scale. Our results show that the local storage measurements are strongly related to streamflow dynamics at larger scales (〉 100 km 2 ; correlation coefficient = 0.78-0.81), but at small scale no such relationship exists (~ 1 km 2 ; correlation coefficients = -0.11). The geologic setting in the region can explain both the disconnection between local water storage and headwater runoff, and the connectivity between headwater storage and streams draining larger catchment areas. More research is required to understand what controls the form of the observed storage-discharge relationships at the catchment scale. This study demonstrates that high-precision gravimetry can provide new insights into the complex relationship between state and response of hydrological systems. Copyright © 2012 John Wiley & Sons, Ltd.

Description: In semiarid regions, the rooting strategies employed by vegetation can be critical to its survival. Arid regions are characterized by high variability in the arrival of rainfall, and species found in these areas have adapted mechanisms to ensure the capture of this scarce resource. Vegetation roots have strong control over this partitioning, and assuming a static root profile, predetermine the manner in which this partitioning is undertaken.A coupled, dynamic vegetation and hydrologic model, tRIBS + VEGGIE, was used to explore the role of vertical root distribution on hydrologic fluxes. Point-scale simulations were carried out using two spatially and temporally invariant rooting schemes: uniform: a one-parameter model and logistic: a two-parameter model. The simulations were forced with a stochastic climate generator calibrated to weather stations and rain gauges in the semiarid Walnut Gulch Experimental Watershed (WGEW) in Arizona. A series of simulations were undertaken exploring the parameter space of both rooting schemes and the optimal root distribution for the simulation, which was defined as the root distribution with the maximum mean transpiration over a 100-yr period, and this was identified. This optimal root profile was determined for five generic soil textures and two plant-functional types (PFTs) to illustrate the role of soil texture on the partitioning of moisture at the land surface. The simulation results illustrate the strong control soil texture has on the partitioning of rainfall and consequently the depth of the optimal rooting profile. High-conductivity soils resulted in the deepest optimal rooting profile with land surface moisture fluxes dominated by transpiration. As we move toward the lower conductivity end of the soil spectrum, a shallowing of the optimal rooting profile is observed and evaporation gradually becomes the dominate flux from the land surface. This study offers a methodology through which local plant, soil, and climate can be accounted for in the parameterization of rooting profiles in semiarid regions.